I for one, would like to have the Mechs feel like 80 tons of badness. I don't want it to feel too quick and action oriented. I don't want Gundam or Armoured Core (nothing bad about those, I love 'em), but this is Battletech. It should feel more like a simulator than an arcade game.
And did I mention that I want to have customisation?
On this topic: each Mech has several standard versions, but you are free to personalise them, as in TT.
Another thing I hope for is that you have air support.
Finally, the Mercenary concept is just too cool to pass up: starting with a 25 ton ricketicky Commando and ending with a lance of Atlases armed to the teeth and some Aerotech overhead. I really love the feeling of progression. This doesn't have to be via a Mercenary-idea, but it is the simplest.
What do you hope for?